The use of portable terminals is rapidly increasing due to their portability, and service providers (terminal manufacturers) are competitively developing portable terminals with convenient functions in order to attract more users.
For example, the portable terminals provide various functions such as a phone book, a game, a scheduler, a Short Message Service (SMS), a Multimedia Message Service (MMS), a Broadcast Message Service (BMS), an Internet service, an Electronic (E)-mail, a morning call, a MP3 (MPEG Audio Layer-3), and a digital camera.
In general, a user of a portable terminal stores personal data, such as directory and schedule data, in the portable terminal. Also, the user stores the personal data in a separate data storage server, in order to be able to store the personal data, stored in the previous portable terminal, intactly in a new portable terminal to be used due to the replacement or loss of the previous portable terminal. If the data stored in the portable terminal or the data storage server are changed, data synchronization should be performed between the portable terminal and the data storage server in order to equalize the data stored in the portable terminal and the data stored in the data storage server.
Herein, the portable terminal and the data storage server detect a change history of stored data to determine data requiring synchronization.
For example, the portable terminal and the data storage server compare specific codes of data to determine the need of synchronization between the data. However, the number of times of the comparison between specific codes increases with an increase in the number of data stored.
Also, if a data synchronization process is to be performed with respect to a plurality of devices, the connection of the devices should be maintained with respect to the data storage server. Thus, if a device requiring a data synchronization process cannot be connected to the data storage server, it is impossible to perform a data synchronization process with respect to the device.
Not only portable terminals but also more home appliances such as televisions (TVs), refrigerators, washing machines and electronic picture frames are connected to a network and evolve into information home appliances. That is, more and more devices can store data and provide a remote data access service. However, it becomes more difficult for users to locate their desired data among the overflowing information. Also, it will be more convenient for users if TVs can be used to search for and display pictures taken by cameras or portable terminals.
What is therefore required is an apparatus and method for synchronizing metadata of stored data (or information about stored data), thus making it easy to search for data in any device connected by a network.